/*
 * Copyright 2009 original author or authors. Licensed under the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License. You may obtain a copy of the License at
 * http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific language governing permissions and limitations under the
 * License.
 */
package cn.configleon.resource;

import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.List;

import cn.configleon.configurer.AbstractPropertyConfigurer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.core.io.Resource;
import org.springframework.util.StringUtils;


public abstract class AbstractPropertyResources implements PropertyResources, ApplicationContextAware {
    
    private static Logger logger = LoggerFactory.getLogger(AbstractPropertyConfigurer.class);
    
    protected String resourcePath;
    
    protected String resourceDefault = "config-default.properties";
    
    protected String resourceNamePrefix = "config";
    
    private ApplicationContext applicationContext;
    
    private String overrideJvmVariableName = "configPropertiesOverride";
    
    /**
     * @param resources The list of resources.
     * @param location The location of the resource.
     */
    protected void addResource(List<Resource> resources, String location) {
        Resource resource = applicationContext.getResource(location);
        
        if (logger.isInfoEnabled()) {
            logger.info("Trying to add resource " + location);
        }
        
        if (resource != null && resource.exists()) {
            resources.add(resource);
            if (logger.isInfoEnabled()) {
                logger.info("Adding resource " + location);
            }
        }
    }
    
    public List<Resource> getResources(String configLocation) throws FileNotFoundException {
        
        List<Resource> resources = new ArrayList<Resource>(1);
        
        String configPropertiesOverride = System.getProperty(overrideJvmVariableName);
        if (StringUtils.hasText(configPropertiesOverride)) {
            if (logger.isInfoEnabled()) {
                logger.info("The " + overrideJvmVariableName + " JVM variable is " + configPropertiesOverride);
            }
            addResource(resources, configPropertiesOverride);
        }
        
        return resources;
    }
    
    protected ApplicationContext getApplicationContext() {
        return applicationContext;
    }
    
    public void setApplicationContext(ApplicationContext applicationContext) {
        this.applicationContext = applicationContext;
    }
    
    protected String getOverrideJvmVariableName() {
        return overrideJvmVariableName;
    }
    
    /**
     * Allow the jvm variable name to be configured (by Spring)
     */
    public void setOverrideJvmVariableName(String overrideJvmVariableName) {
        this.overrideJvmVariableName = overrideJvmVariableName;
    }
    
    public String getResourcePath() {
        return resourcePath;
    }
    
    public void setResourcePath(String resourcePath) {
        this.resourcePath = resourcePath;
    }
    
    public String getResourceDefault() {
        return resourceDefault;
    }
    
    public void setResourceDefault(String resourceDefault) {
        this.resourceDefault = resourceDefault;
    }
    
    public String getResourceNamePrefix() {
        return resourceNamePrefix;
    }
    
    public void setResourceNamePrefix(String resourceNamePrefix) {
        this.resourceNamePrefix = resourceNamePrefix;
    }
    
}
